Electronic counter



y 1949- w. A. GIESEKE 2,470,926

ELECTRONIC COUNTER Filed Feb. 27, 1946 2 Sheets-Sheet l May 24, 1949. w.A. GIESEKE ELECTRONIC COUNTER 2 Sheets-Sheet 2 Filed Feb. 27, 1946 AMA,Ali'- ernaf Z dz'aseke Patented May 24, 1949 UNITED STATES PATENT OFFICEELECTRONIC COUNTER Werner A. Gieseke, Danville, Ill.

Application February 27, 1946, Serial No. 650,663

Claims. 1

My invention relates to electronic counters and more particularly to ahigh speed device employing light interruptions on a phototube as ameans of setting up impulses in an electronic circuit which areeffective to cause the operation of a counting mechanism of anycharacter.

One object of the invention is to provide a counter of the characterindicated in which the electronic means are operated by direct current,thus enabling a connected, mechanical register ing device to be operatedat high speed.

A further object is to provide an electronic counter arranged to convertshort electrical impulse set up objects moving at high speed intoimpulses of longer duration that allow for the inertia of and arecapable of operating the mechanical parts of the counter.

A further object is to devise a counter characterized by the abovefeatures in which the impulse broadening stage acts as a trigger for thepower stage of the circuit which is coupled to electrical means foroperating the registering mechanism of the counter.

These and further objects of the invention will be set forth in thefollowing specification, reference being had to the accompanyingdrawings, and the novel means by which said objects are efiectuated willbe definitely pointed out in the claims.

In the drawings:

Fig. l is a schematic arrangement showing one method of passing theobjects to be counted through the focal point of light rays incidentupon a phototube which forms part of an electronic circuit.

Fig. 2 shows a variant method of presenting the objects to be counted tothe optical system of the counter.

Fig. 3 illustrates a circuit layout which may be used with either of thearrangements shown in Figs. 1 and 2.

Referring to Fig. 1, the numeral I0 designates a hopper into which thearticles to be counted may be deposited manually or mechanically. Thehopper includes a delivery passage H arranged for gravity feed of thearticles and sized to permit only the flow of single articles one behindthe other. Each article is dropped through the focal point 12 of anoptical system comprising a light source !3 Whose rays are focused by alens I4 for incidence on a phototube I5. Each interruption of the rayson the phototube generates an electrical impulse that is transmitted toan amplifying circuit, generally indicated by the numoral it, which inturn conditions the impulse so that it may be employed to set inoperation a counting mechanism ll, all as specifically explainedhereinafter in connection with the circuit arrangement shown in Fig. 3.

In 2, the articles l8 to be counted are deposited in any desired manneron a conveyor 59 which carries the articles successively through thefocal point of an optical system comprising a ight source and a lens 2!.The conveyor belt characterized by sufficient transparency to enable thelight rays to become incident on a photo tube 22 which is related to anamplifying circuit 2.3 and a counting mechanism 2d to accomplish generaloperation noted above and as presently described in detail.

The circuit arrangement for effecting the counting action is illustratedin Fig. 3. Generally speaking, the capacity to count at high speed, i.e., as many as one thousand pieces per minute, is due to direct currentoperation of the circuit stages including the phototube which sendsnegative impulses to an amplifier that is coupled to a trigger circuitwhich in turn is connected to a power stage, the latter controllingoperation of a mechanical counter through a solenoid, for example, orany type of control mechanism and is particularly suitable forcontrolling those devices which are characterized by rapid, cyclingmotions.

Specifically, a power source for the phototube and amplifying phases ofthe circuit is provided by a transformer 25 having a primary Winding 26and secondary windings 27, 28 and 29. The winding 27 is connected to thedirectly heated cathode of a duo-diode tube 30 while the plates of thistube are respectively connected to the terminals of the winding 28. Alsoconnected to one terminal of the winding 21 is a wire 3i including inseries relation a fuse 32 and a choke coil 33 whose end is connected toground by a wire 34 which includes a capacitor 35. The winding 28 iscenter tapped by a wire 3E which connects with the wire 34. Thisarrangement provides a full wave rectifier employing an L-type filterconstituted by the coil 33 and capacitor 35 which supplies directcurrent voltage for the operation of the stages involving a phototube36, a pentode amplifier 3'! which in conjunction with the associatedcircuit acts to invert impulses generated by the phototube 36, and athyratron tube 38 which in conjunction with the associated circuitbroadens the impulses received from the amplifier and acts as a triggerfor the power stage of the circuit which is separately supplied bydirect current as hereinafter described.

Leading from the junction of the wires 3| and 34 is a wire 39 andconnecting the latter to ground is a voltage divider 49 comprising fixedresistors 43, 4 2 and 43, and a potentiometer 44. A wire 45 connects thepotentiometer 44 with the oathode of the amplifier 31 while the plate ofthe latter is connected by a wire 45 having a fixed resistor 4'! withthe wire 39. The cathode of the phototube 36 is connected to ground by awire 48 having a fixed resistor 49 while the anode of the phototube isconnected to the voltage divider 49 between the resistors 42 and 43. Thecontrol grid of the amplifier 3'! is connected to ground by a wire ithrough a resistor 52 and a capacitor 53 is bridged between the wires 48and 5i on the output ends of the resistors 49 and 52. The resistor 52and capacitor 53 function as a grid leak bias for the control grid ofthe amplifier 31.

A wire 54 having a resistor 55 provides connection between the controlgrid of the trigger tube 38 and the wire 46 at a point between the plateof the amplifier 31 and the resistor 41. The cathode of the trigger tube38 is connected to a filter comprising a resistor 56 and a capacitor 51and the plate of the trigger tube is connected by a wire 59 to the wire39. Also connected to the wire 39 and in parallel with the trigger tube38 is a wire 6| which includes a resistor 62. The lower end of the wire6! is connected to a wire 63 which at one end connects with the filter56-51 and at the opposite end with the power driving stage presentlydescribed, and also with a wire 64 including a resistor 65 which leadsto ground.

It will be understood that the terminals of the secondary winding 29 areconnected to the filament of the amplifier 3'! and that this winding iscenter tapped at 66 for connection to the amplifier cathode. For thefilament of the trigger tube 38, a separate transformer 61 is usedhaving primary and secondary windings 68 and 69, respectively. Theterminals of the secondary winding 69 are connected to the filament ofthe trigger tube 38 while a center tapping of this winding connects withthe cathode of the trigger tube. For the sake of clearness, theconnections referred to in this paragraph have not been illustrated inthe drawing.

A separate transformer H is employed for the power driving stage of thecircuit and it comprises a primary winding 12 and secondary windings i3,i4 and 15. The terminals of the winding 13 are connected to the platesof a duo-diode tube 16 whose cathode is connected to the upper end of avoltage divider 11 comprising the fixed resistors 18 and 19 andpotentiometer 80. A wire 8! connects the potentiometer 80 with thecathode of a Vacuum type power tube 82 which constitutes the powerdriving stage of the circuit and whose plate is connected to one end ofthe coil of a solenoid 83, the opposite end of the coil being joined toa wire 84 that connects with the upper end of the voltage divider I1 andwith the cathode of the tube 16. It will be understood that the core ofthe solenoid is suitably related to the counting mechanism I! or 24 sothat the latter will be actuated when the core is shifted in the mannerhereinafter described.

The secondary winding 73 is center tapped by a wire 85 which connectswith the input end of the potentiometer 80. Capacitors 86 and 81 areres'pectively interposed between the wire 85 and the upper end of thesolenoid coil, and between the wires 85 and 8|. The potentiometer andcapacitor B! constitute a variable cathode, resistorcapacitor filter forproviding a variable cathode biasing of the power tube 82 to establishthe correct operating point for the solenoid 83. From the foregoing, itwill be obvious that the tube 16 and associated circuit provides a fullwave rectifier employing a resistor-capacitor filter for supplyingdirect current voltage for the operation of the power tube 82 and thesolenoid 83.

The power and amplifying stages of the circuit are linked by a resistor88 which connects the output end of the resistor 56 with the controlgrid of the power tube 82 and by the wire 63 which connects with thewire 85.

The terminals of the secondary winding 14 are connected to the filamentof the power tube 82 and the same winding is center tapped by a wire 89which connects with the power tube cathode. Power for the light source!3 or 20 may be supplied by the secondary winding I5. The connec tionsreferred to in this paragraph, including the light source, are not shownin the drawing for the sake of clearness.

The operation of the circuit shown in Fig. 3 will now be described inconnection with the article feeding and optical system shown in Fig. 1,it being understood that the circuit functions in an identical mannerfor the arrangement illustrated in Fig. 2.

So long as light rays from the source [3 are incident on the phototube36, the amplifier 31 conducts normally by reason of the variable cathodebias provided by the potentiometer 4i and the grid leak bias constitutedby the resistor 52 and capacitor 53. However, when an article to becounted passes through the focal point of the optical system shown inFig. 1, the shadow cast on the phototube 36 interrupts the conduction ofelectrons therethrough and the potential at the top of resistor 49,normally positive, drops to that of ground. Then through the action ofthe capacitor 53 and resistor 52, an impulse of negative polarity issent to the control grid of amplifier 3! so that the conductance of thelatter dcreases and its plate voltage increases for the duration of theincoming impulse from the phototube.

It will be noted that regardless of the size or shape of the object tobe counted, the negative impulse fed, to the control grid of theamplifier 31 retains its standard size because of the time constantcharacteristics of the resistor-capacitor combination 52-53, or, inother words, the phototube always sends the same impulse regardless ofthe time interruption of the light rays with respect to any given valuesof the resistor 52 and capacitor 53.

The trigger tube 38 is normally not ionized due to the grid biasdeveloped across the resistors 41 and 55 and by the cathode biasdeveloped across the resistors 59 and 62, i. e., during periods of lightincidence on the phototube. However, when conductance through theamplifier 3'; decreases as above described, the voltage drop across theresistor 4? also reduces and the grid bias of the trigger tube 38 isdriven towards zero and slightly in a positive direction. Hence, duringperiods of light interruption, the amplifier 3'! and the associatedcircuit acts as an impulse inverter, changing the negative going, inputimpulse to a positive going, output impulse which triggers the tube 38as will be presently described. The amplifier also has impedancematching characteristics which match the output of the phototube to theinput of the trigger tube.

The positive impulse from the plate of the amplifier 31 causes thetrigger tube 38 to ionize and the current flow through the cathoderesistors 56 and 65 causes the cathode of the tube 38 to go morepositive for the duration of the incoming impulse and this positivegoing, cathode voltage is fed to the control grid of the power tube 82which thereby becomes ionized. When the power tube 82 fires, currentflow through its plate circuit is increased sufiiciently to energize thesolenoid 83 which may be hooked with a suitable counting or controlmechanism.

Normally, the power tube 82 is biased by resistors 56 and 88, and by thepotentiometer 80, but when the trigger tube 38 ionizes, this bias isdriven towards zero. It will be understood that the trigger tube 38 maybe or may not conduct when the phototube is illuminated, depending uponthe biasing of the tube 38, but, whatever the situation may be in thisrespect, the latters conductance increases when an impulse is fed to itscontrol grid as above described. The trigger tube 38 and the associatedcircuit function as the impulse broadening stage and is responsible forlengthening the time duration of the impulse fed to the power tube 82sufiiciently to effect the operation of the counting or registeringdevice.

The general object of the entire circuit is to supply a constant impulseto the tube 82 representing the power stage and, to this end, theamplifier 3'! feeds a short impulse to the trigger tube 38 which in turnsupplies an impulse of longer duration to the power tube.

The specific advantage of that portion of the circuitwhich includes thetrigger tube 38 centers in the cathode filter constituted by theresistor 58 and capacitor 51. Although the impulse fed to the triggertube 38v may be of short duration, after which this tube may deionize,the time constant of the capacitor-resistor network 51-56 actuallycontrols the width of the impulse fed to the power tube 82. When thetube 33 ionizes, its cathode goes positive and when it deionizes, thecapacitor 51, which was charged when this tube ionized, dischargesthrough the resistor 56 to keep the cathode of the tube 38 at that morepositive potential for a time controlled by the characteristics of the51-56 network.

The trigger tube 38 is deionized by lowering its plate-to-cathodepotential to a value equal to the extinction potential of the tube. Whenthe tube 38 fires, the heavy conducton therethrough increases theresistance drops across the resistors 56 and 65, the latter forming partof a voltage divider including the resistor 62 which is connected to thepower supply wire 39 and hence to the plate of the tube 38. Sinceincreased conduction through resistor 56 renders the upper end thereofmore positive with respect to the opposite end, which ends arerespectively connected to the cathode of the trigger tube and throughthe voltage divider including the resistor 62 to. the plate of the sametube, the cathode becomes more positive with respect to the plate, thusreducin the plate-to-cathode potential to a value equal to thedeionizing potential.

It is thus possible to control the time duration of the impulse firingthe power tube 82 as necessitated by the time delay required for theoperation of the associated mechanical device before the solenoid 83 isdeenergized. In other words, without this time delay or impulsebroadening and by reason of the short impulse set up by an articlemoving through the optical system, there would not be sufficient timefor the counter, due to its inertia, to perform its allotted task. Myimproved arrangement therefore is particularly suitable for high speedcounting, including those articles which are too light in weight toactuate a conventional switch or trigger.

It will be understood that the values of the resistors and capacitorswill be adjusted and related as the particular operating circumstancesrequire.

I claim:

1. In a device for registering the passage of a succession of articles,the combination of an optical system comprising a light source and aphototube for receiving rays from the source, means arranged to pass thearticles through the focal point of the system, direct current operated,electronic means associated with the phototube comprising means forinverting impulses set up by the phototube when the light rays thereonare interrupted by a passing article, a trigger tube for receiving theinverted impulses and a power tube fired by the trigger tube, aresistorc'apacitor filter associated with the cathode of the triggertube and the control grid of the power tube whereby the time duration ofeach impulse fed to the power tube is lengthened, and solenoid meansconnected to the plate of the power tube and energized by the firing ofthe power tube, and the solenoid means being adapted for connection to aregistering device.

2. In a device for registering the passage of a succession of articles,the combination of an optical system comprising a light source and aphototube for receiving rays from the source, means arranged to pass thearticles singly through the focal point of the system, direct currentoperated, electronic means comprising an amplifier, a resistor-capacitorcouplin associated with the cathode of the phototube and the controlgrid of the amplifier whereby an impulse of constant size is fed to andis inverted by the amplifier when the light rays on the phototube areinterrupted by a passing article, a trigger tube for receiving theinverted impulse and a power tube fired by the trigger tube, aresistor-- capacitor filter associated with the cathode of the triggertube and the control grid of the power tube whereby the time duration ofeach impulse fed to the power tube is lengthened, and solenoid meansconnected to the plate of and energized by the firing of the power tube,the solenoid means being adapted for connection to a registering device.

3. In a device for registering the passage of a succession of articles,the combination of an optical system comprising a light source and aphototube for receiving rays from the source, means arranged to pass thearticles singly through the focal point of the system, a normallydeionized, power tube, solenoid means having its coil in series with theplate of the power tube and adapted for connection to a registeringdevice,

means for supplying direct current voltage to the power tube and directcurrent operated, electronic means responsive to impulses set up by thephototube when the light rays thereon are interrupted by a passingarticle and associated with the power tube, said electronic meanscomprising means for inverting the impulses and a trigger tube forreceiving the inverted impulses and feeding them to the power tube forfiring the same, and a resistor-capacitor filter associated with thecathode of the trigger tube and the control grid of the power tubewhereby the time duration of each impulse fed to the power tube islengthened sufiiciently to enable the solenoid means to actuate theregistering device.

4. In a device for registering the passage of a succession of articles,the combination of an optical system comprising a light source and aphototube for receiving rays from the source, means arranged to pass thearticles singly through the focal point of the system, a normallydeionized, power tube, solenoid means having its coil in series with theplate of the power tube and adapted for connection to a registeringdevice, means for supplying direct current voltage to th power tube, anddirect current operated, electronic means responsive to impulses set upby the phototube when the light rays thereon are interrupted by apassing article and associated with the power tube, said electronicmeans comprising an amplifier, 2, resistor-capacitor coupling associatedwith the cathode of the phototube and the control grid of the amplifierwhereby an impulse of constant size is fed to and is inverted by theamplifier when the rays are interrupted, a trigger tube for receivingthe inverted impulses and feeding them to the power tube for firing thesame, and a resistor-capacitor filter associated with the cathode of thetrigger tube and the control grid of the power tube whereby the timeduration of each impulse fed to the power tube is lengthenedsuificiently to enable the solenoid means to actuate the registeringdevice.

5. A device for counting impulses of short duration comprising aphototube intermittently subjected to light rays, direct currentoperated, electronic means associated with the phototube comprisingmeans for inverting impulses set up by the phototube when the light raysthereon are interrupted, a trigger tube for receiving the invertedimpulses and a power tube fired by the trigger tube, aresistor-capacitor filter associated with the cathode of the triggertube and the control grid of the power tube whereby the time duration ofeach impulse fed to the power tube is lengthened, and a counter havingan actuating coil with inductive characteristics connected to the plateof and energized by the firing of the power tube.

6. A device for counting impulses of short duration comprising aphototube intermittently subjected to light rays, direct currentoperated, electronic means associated with the phototube comprising anamplifier, a resistor-capacitor coupling associated with the cathode ofthe phototube and the control grid of the amplifier whereby an impulseof constant size is fed to and is inverted by the amplifier when thelight rays on the phototube are interrupted, a trigger tube forreceiving the inverted impulses and a power tube fired by the triggertube, a resistor-capacitor filter associated with the cathode of thetrigger tube and the control grid of the power tube whereby the timeduration of each impulse fed to the power tube is lengthened, and acounter having an actuating coil with inductive characteristicsconnected to the plate of and energized by the firing of the power tube.

7. A device for counting impulses of short duration comprising aphototube intermittently subjected to light rays, a normally deionized,power tube, a counter having an actuating coil with inductivecharacteristics in series with the plate of the power tube, means forsupplying direct current voltage to the power tube and direct currentoperated, electronic means responsive to impulses set up by thephototube when the light rays thereon are interrupted and associatedwith the power tube, said electronic means comprising means forinverting the impulses and a trigger tube for receiving the invertedimpulses and feeding them to the power tube for firing the same, and aresistor-capacitor filter associated with the cathode of the triggertube and the control grid of the power tube whereby the time duration ofeach impulse fed to the power tube is lengthened sufiiciently to effectoperation of the counter.

8. A device for counting impulses of short dura tion comprising aphototube intermittently subjected to light rays, a normally deionized,power tube, a counter having an actuating coil with inductivecharacteristics in series with the plate of the power tube, means forsupplying direct current voltage to the power tube and direct currentoperated, electronic means responsive to impulses set up by thephototube when the light rays thereon are interrupted and associatedwith the power tube, said electronic means comprising an amplifier, aresistor-capacitor coupling associated with the cathode of the phototubeand the control grid of the amplifier whereby an impulse of constantsize is fed to and is inverted by the amplifier when the rays areinterrupted, a trigger tube for receiving the inverted impulses andfeeding them to the power tube for firing the same, and aresistor-capacitor filter associated with the cathode of the triggertube and the control grid of the power tube whereby the time duration ofeach impulse fed to the power tube is lengthened sufficiently to efiectoperation of the counter.

9. In an apparatus for courting impulses of short duration including aphototube intermittently subjected to light rays, an amplifier, aresistor-capacitor coupling associated with the cathode of the phototubeand the control grid of the amplifier whereby an impulse of constantsize is fed to and is inverted by the amplifier when the light rays onthe phototube are interrupted, a trigger tube responsive to the invertedimpulses, a power tube fired by the trigger tube, a resistorcapacitorfilter associated with the cathode of the trigger tube and the controlgrid of the power tube whereby the time duration of each impulse fed tothe power tube is lengthened, and a counting device in the outputcircuit of the power tube.

10. In an apparatus for lengthening impulses of short duration to enabletheir being counted by a counting device including a phototube inter-.mittently subjected to light rays, an amplifier, a resistor-capacitorcoupling associated with the cathode of the phototube and the controlgrid of the amplifier whereby an impulse of constant size is fed to andis inverted by the amplifier when the light rays on the phototube areinterrupted, a trigger tube responsive to the inverted impulses, a powertube fired by the trigger tube and arranged for connection to thecounting device, and a resistor-capacitor filter associated with thecathode of the trigger tube and the control grid of the power tubewhereby the time duration of each impulse fed to the power tube islengthened.

WERNER A. GIESEKE.

(References on following page) REFERENCES CITED Number Name Date2,252,457 Cockrell Aug. 12, 1941 i t; i g gi fs are Of record in the2,342,753 Pearson et a1 Feb. 29, 1944 p 2,421,991 Carriere June 10, 1947UNITED STATES PATENTS 5 2,432,084 Blair Dec. 9, 1947 Number Name DateOTHER REFERENCES 1,998,132 Geficken et a1 Apr. 16, 1935 2,049,376Hertwig et a1 July 28 1936 Electncal Countmg by W. B. Lewls (pages 63-2,140,350 Dawson 13 1938 64) Published by The Macmillan

